FRESHWATER ALGÆ FROM TUDDAL IN TELEMARK. 157 



further development of the Stigonema-specimens observed, but 

 it would be highly interesting to follow the development of the 

 simple filaments. For the rest I think that the drawings given 

 are more illustrative than a long description. 



Fig. 2. 268 & 590 diameters. 



Glass JPeridineæ, 



Family Gymnodiniaceæ. 

 Genus Amphidinium. Glap & Lachm. 1858. 

 27. Amphidinium lacustre. Stein: Organismus. * 



Very rare, only observed in a single case, but perhaps over- 

 looked owing to its minute size. Size: long 21 u, lat. 17 71. 



